power save mode for battery in Fedora 19.

I was getting really bad battery life on my Fedora 19 system, and did not find much on how to tune it. Finally I found something that just does not need much configuration but works pretty well. So, here is what you need to do:

sudo yum install tuned tuned-adm

The second package, tuned-adm installs additional themes for power saving. It is optional and not mandatory. Once you have installed these, you can do the following:

configure firewall – the easy way.

It is good practice to keep iptables/firewall enabled. But configuring it is difficult, do you agree. Not any more 🙂

Install firewall-config

sudo yum install firewall-config

This will install a GUI application, which you can run with “Firewall” application in the dash or with “firewall-config” in terminal. It is pretty straight forward to use this tool, even if you don’t have much knowledge on Firewall/iptables.

ss – anothre utility to investigate sockets.

ss is :

ss  is  used to dump socket statistics. It allows showing information similar to netstat.  It can display more TCP and state informationsthan other tools.

 

This comes in iproute package in Fedora. So, to install this you would need to install “iproute” if not installed already.

sudo yum install iproute

Now, once you have done that you can look at the man page to check what all you can see with ss. but here are some examples:

slow ssh connection

If you are experiencing slow ssh connections, then possibly your system is trying to do reverse lookup of the IP address. If that is the case, then you can add the below to “hosts” line in /etc/nsswitch.conf file.

‘[NOTFOUND=return]’

The other cause for slow connections can be GSSAPI authentication. If that is the case, then the simplest solution is to add the following in your “~/.ssh/config” file:

Allow incoming/outgoing ports on iptables

Last couple of years, I just used to disable iptables on my system, this time I decided not to disable it and keep it enabled.

So far so good, now comes the tricky part, I have http server enabled on my system and since this is on local network with already firewall and other security in place so I can allow all incoming to my system and similarly I need to enable XDMCP outgoing. So, I can add the rules like this :

unable to browse windows network with samba4

I use Fedora 17 on my work laptop and thus need to connect to windows share sometimes. After I upgraded to Fedora 17 some time, I was unable to browse the windows network. I would get all kind of errors and warnings and tried everything that I knew about Samba to fix the issue. Tried searching through all the forums to figure out what was wrong but nothing helped. And suddenly today I resolved it and guess how:

ss – utility to investigate sockets.

Sometimes, you find some interesting application/command by accident, and that is just what happened a few days back. Well, I was doing a ssh and as usual made my share of mistake in typing and missed the “h” from the ssh command and saw a list of options instead of my prompt on remote server.

Now, that set me thinking and fond that its a very interesting command that comes with iproute on Fedoara, so if you want this command, then install iproute like this